GOP front-runner Donald Trump, who has maintained a stronghold on first place in the polls, saw an 11% drop in his odds for winning the GOP nomination in CNN's Political Prediction Market. Trump's slide corresponded with a rise in winning odds for Florida Sen. Marco Rubio.

CNN's Political Prediction Market, administered by a company called Pivit, is game that factors polls and other elements and invites users to predict where the election will go. The markets change as the public weighs in on the increasing or decreasing chance that a candidate or party wins or loses an election. It should not be confused as a survey from real voters.

Riding the coattails of first place odds is Texas Sen. Ted Cruz, who is also neck-and-neck with Trump in the polls.

The odds for the Republicans winning the presidency also seem to be slipping. The odds for a Democratic presidency are currently at 59%, while Republicans' chances of winning are 41%.

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For the Democrats, Hillary Clinton's odds are substantially higher than rival Bernie Sanders. Clinton's odds are currently at 93% and Sanders is at 9%.